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888

Appendix II.

I I

I.   ENTROPY OF WATER FROM 32 FAHR.

PER LB. WEIGHT.

t*
	r
	

32
	492
	

50
	5io
	

IOO
	560
	

15
	610
	

2OO
	660
	

250
	710
	

300
	760
	

35
	810
	

400
	860
	

*oco

036

J29
'21 ^

295
367
438
'54
566

We have next to find the additional entropy due to the conver
sion of water into steam. Now at any temperature rx the sensible
heat from 32 is the area SH, and the heat to be supplied in making
this into steam being area Lh, the entropy added = LK -r r  <j>s.
In this manner the second curve c D has been drawn and the
figures in Tables II. and III. obtained:

II. ENTROPY OF STEAM
PER LB. WT.

III. ENTROPY OF STEAM AND
WATER PER LB. WT.

r
	_k
 T

492
	2*219

510
	2*116

560
	1-865

610
	1 655

660
	1-476

710
	1*322

760
	1-188

810
	1*070

860
	965

r
	0w-f0s

492
	2*2f9

510
	2*188

560
	1*994

610
	1-870

660
	1*771

710
	1*691

760
	1*626

810
	i '574

860
	i*53i

'Hie next problem is  to convert an ordinary j> V indicator
01 into a r$ diagram, which we shall here solve by the